From df8f074cf614aeffc127c6f60317b7a6f80bbf63 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sun, 21 Feb 2021 11:40:35 +0100
Subject: [PATCH] LibJS: Make TypedArray::data() return a Span<T>

This inserts bounds checking assertions whenever we're reading/writing
a typed array from JS.
---
 Userland/Libraries/LibJS/Runtime/TypedArray.h | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/Userland/Libraries/LibJS/Runtime/TypedArray.h b/Userland/Libraries/LibJS/Runtime/TypedArray.h
index 4e29ef6fd6..a0f6709a76 100644
--- a/Userland/Libraries/LibJS/Runtime/TypedArray.h
+++ b/Userland/Libraries/LibJS/Runtime/TypedArray.h
@@ -50,7 +50,7 @@ public:
     virtual size_t element_size() const = 0;
 
 protected:
-    TypedArrayBase(Object& prototype)
+    explicit TypedArrayBase(Object& prototype)
         : Object(prototype)
     {
     }
@@ -116,7 +116,14 @@ public:
         }
     }
 
-    T* data() const { return reinterpret_cast<T*>(m_viewed_array_buffer->buffer().data()); }
+    Span<const T> data() const
+    {
+        return { reinterpret_cast<const T*>(m_viewed_array_buffer->buffer().data()), m_array_length };
+    }
+    Span<T> data()
+    {
+        return { reinterpret_cast<T*>(m_viewed_array_buffer->buffer().data()), m_array_length };
+    }
 
     virtual size_t element_size() const override { return sizeof(T); };
 
@@ -127,7 +134,7 @@ protected:
         ASSERT(!Checked<u32>::multiplication_would_overflow(array_length, sizeof(T)));
         m_viewed_array_buffer = ArrayBuffer::create(global_object(), array_length * sizeof(T));
         if (array_length)
-            ASSERT(data() != nullptr);
+            ASSERT(!data().is_null());
         m_array_length = array_length;
         m_byte_length = m_viewed_array_buffer->byte_length();
     }